Vacuum tank



H. B. COATS VACUUM TANK Filed Feb. 6, 1922 INVENTOR. 7/6/72) 5. 66/9712 ATTORNEYS.

June 3, 1924.

atented June 3, 1924.

TIEHZTNRY B. COATS, 0F VEEDERSBUBG, INDIANA.

VACUUM TANK.

Application filed February 6, 1922. Serial No. 534,635.

T 0 all whom it may concern:

Be it known that I, HENRY B. Come, a citizen of the United States, and a resident of Veedersburg, county of Fountain, and State of Indiana, have invented a certain new and useful Vacuum Tank; and I do hereby declare that the following is a full, clear, and eXact description thereof, reference being had to the accompanying drawings, in which like numerals refer to like parts.

This invention relates to a vacuum tank for drawing liquid fuel therein from a main supply tank, by suction, and delivering it to a motor by gravity. 7

One feature of the invention resides in the automatic suction control, whereby the suction conduit connecting the motor intake manifold with said tank is varied by the variation in the vacuum produced by said motor, so that the vacuum will be accommodated to the requirement of the engine for fuel. In the usual type of vacuum tank, the vacuum passageway is necessarily reduced to a comparatively small diameter, so that under a high vacuum pressure too much air will not be drawn into the manifold so as to distribute the proper gaseous mixture. Therefore, when a motor is run ning at an extremely high speed or pulling up a long hill, the motor will be starved for fuel because under such conditions the vacu um will be at a minimum pressure and the fuel consumption will be at a maximum. It is that difiiculty which is sought to be remedied bythisinvention. means of this arrangement under the circumstances above noted, the suction conduit is comparatively large in diameter, so that the maximum vacuum pressure may be obtained within the tank for sucking a maximum quantity of fuel therein for feeding the motor at a high speed or on a long pull; and when the motor is at a slow speed, or in other words using the minimum amount of fuel and give the maximum vacuum pressure, said passageway will be closed and the suction drawn through a bypass of a comparatively small diameter so as not to draw into the manifold such a quantity of air as will set the proper mixture. Of coursefwhen the motor is running at high speed, the suction of additional air through the vacuum tank will not affect the mixture, and in fact would be of some benefit.

Amotl er feature of the invention resides in the construction of the float chamber or inner chamber contained Within the vacuum chamber for enclosing the air inlet valve, whereby said chamber may be mounted in connection with the top of the vacuum chamber so as to be closed at the top and be provided with a small opening between the top of the float or valve actuating member and top of the chamber through which the fuel may pass when it reaches the desired height in the vacuum chamber, for actuating the float or valve actuating member. This chamber encloses the vacuum passage so that the fuel contained in the vacuum chamber will be prevented from being drawn through said passage under any conditions, particularly when it is thrown against the top of the chamber by the shaking of the tank.

The full nature of the invention will be understood from the accompanying drawings and the following description and claim. v

In the drawings, Fig. 1 is a central vertical section taken through the tank and a portion of the intake manifold illustrating one type of tank, with the automatic suction control therein. Fig. 2 is the same as Fig. 1 showing the tank construction above mentioned with the double valve control for the air vent and suction line. Fig. 3 is a section taken through the suction inlet showing a modified form of automatic suction control valve. r

In the drawings there is shown a vacuum tank comprising a cylindrical housing 10 enclosing a supply chamber 11 in the lower portion thereof which is separated from a vacuum chamber 12 in the upper portion thereof, by a partition 13 which is secured againstthe annular bead 14 in said casing. Mounted on the top of said casing, there is a cap 15 from which depends a float chamber 16. Communicating with the bottom of the supply chamber 11, there is a pet cock 17 for draining the same and a fuelfeed 18 adapted to be connected with the carbureter of the motor. The vacuum chamber 12 communicates with the chamber 11 through a depending tube 19 having an upturned end on which is loosely mounted a cap valve 20, and the float chamber 16 is similarly provided with a depending tube 21 having a cap valve 22 loosely mounted on its upturned end. This arrangement permits the fuel contained in the float tank to pass into the vaeu umtank when the level in the latter tank. falls below the level in the former, and permits the fuel contained in the vacuum tank to pass into the supply tank, at the same time preventing air or fuel being sucked from the supply tank into the vacuum tank by the vacuum created therein. The supply tank is provided with an air inlet consisting of a tubular passage 23 extending from the cap 15 into said tank whichcommunicates with the chamber 24 having a downwardly turned vent 25.

Mounted in the cap 15, there is a fuel supply line 26 communicating with an opening 27 in said cap so that fuel may be drawn 1 therethrough into the vacuum chamber.

On the other side of the cap 15, there is a vacuum or suction tube 28 connected at one end to the intake manifold 29 of the motor and at the other end connected with a nipple 30 through which suction may be had for producing a vacuum and drawing the fuel into the vacuum tank, as will be hereinafter more fully described. Contained within the float chamber, there is a float 31v mounted on a valve stem 32 which extends through an opening 33 in the cap 15 and has secured on the upper end there of a valve 34. The valve 34 and opening 33 are enclosed within the chamber 35 which communicates with the atmosphere through a downwardly turned tube or air vent 36. The float chamber 16 is provided with peripheral slots 37 and an opening 38 at the top thereof. By means of this arrangement, the valve 34 will be normally closed, shutting off the air supply to said chamber. The suction produced through the tube 28 will draw the fuel into the vacuum chamber until the fuel reaches the peripheral slots 37 or the opening 38. At this level the vacuum chamber and the supply chamber are substantially filled and the fuel will then flow into the float chamber which has heretofore been omitted. After a suflicient quantity of fuel has flown into the float chamber. the float will be raised so as to openthe valve 34 and permit air to enter the float and vacuum chamber, which will break the vacuum and prevent more fuel from being drawn therein.

Heretofore it has been customary to have a comparatively small passageway between the vacuum chamber and suction pipe, so

that the quantity of air drawn into the manifold will not interfere with the proper mixture of gas and air, and also to prevent raw. fuel from being drawn therethrough and any ignition to take place. Such construction often starves the motor wherein p the fuel is withdrawn from the tank faster than it is supplied thereto by reason of this reduced passageway. To overcome this difiiculty, there is provided herein an enlarged passageway 39 extending through the nipple 30 and having a reduced bypass 40, said by-pass being substantially the size of the usual opening. Said passageway and by-pass communicate with a chamber 41 in which there is seated a ball valve 42. Said chamber communicates with the float and vacuum chambers through a plurality of comparatively small passageways 43. When the motor is running slowly under normal running condi tions, there is a maximum of vacuum pressure produced and a minimum of fuel used. In this event the high vacuum pressure will draw the ball valve 42 upwardly against the end of the passage 39. so that it will seat therein and be held against the opening of said passage by the high vaccum pressure so as to shut off the passage 39.

thereby necessitating the use of the small by-pass 40 so that an excess amount of air will not be drawn into the motor. Under these conditions thevacuum passage is non mahbeing substantially the same as those now in use. However. when the motor speeds up or pulls up a long incline, the vacuum will be greatly reduced and the fuel consumption greatly increased. Under these conditions it is desirable to have as large an opening as possible so as to create a greater suction in the vacuum chamber and draw fuel therein more rapidly. This decrease in the vacuum pressure will permit the ball valve 42 to drop back in the position shown herein so as to open the passage 39 which is sufiieiently large to per mit the reduced vacuum pressure to draw an. increased amount of fuel into the tank for properly serving the consumption by the motor. In this instance it is immaterial that air be sucked into the motor in any quantity. since at the high speed, or with the heavy use of fuel. additional air will facilitate rather than detract from the operation thereof.

In the modified form shown inFig. 3, the ball valve 42 is replaced by a valve 142 mounted on the stem 143.

In the construction shown in Fig. 2, the casing 10 is partially surrounded by an auxiliary air jacket 50 which extends down below the partition 13 and is sealed about its lower edge to the chamber 10 at 51. In this construction the casing 10 is smaller at the top than at the bottom; whereas the surrounding jacket 50 is substantially cylindrical, so that whereas the lower end of the jacket fits snugly about and is sealed against said casing at the point 51, the intermediate space between the casing and jacket increases toward the top. There are provided openings or passageways 52 in the wall 10 below the bottom 13, so that the supply chamber 11 will communicate with the space 53 between said jacket and casing. The downwardly extending air vent tube 25 is mounted on the cap 15 and communicates with the air when a small standpipe is provided for the air vent upon the tank containing substantially its full capacity of fuel. This construction also simplifies the manufacture of such a device.

In Fig. 2 there is shown the float valve stem 32 having a valve 34: thereon for opening and closing the air passage 83 from the vent 36 into the floatchamber and vacuum chambers. Mounted on said stem on the opposite side of the passage 33 from the valve 34, there is a valve adapted to seat in a conical recess in the under side of the cap 15 when the air valve is open. W hen the valve 34- is opened by the upward movement of the float 31, the valve 55 will close the passage 33 simultaneously by the same movement of the valve stem. For permitting the air to enter the vacuum chamber, there is a by-pass 56 communicating with the passage 34 and the float chamber, bypass ing the valve 55 so that air may be readily admitted to said chamber, although the valve 55 is closed. Connecting the suction chamber 41 with the vacuum chamber, there is apassage 57, said passage extending through the cap 15 to the conical seat of the valve 55. By means of this arrangement, when the air valve 3% is closed, the passage 57 is open so that the vacuum will be produced within said chamber. Upon the fuel drawn therein reaching a predetermined height so as to overflow into the float tank 16 and elevate the float 81, the air valve 34: will be opened so as to permit air to enter said chamber and the valve 55 will be closed so as to shut oil any further suction through the passage 57 and vacuum tube 28. This will prevent raw air from being sucked into the motor and disturbing proper moisture therein.

The invention claimed is:

In a vacuum tank, the combination with the intake of an internal combustion engine, of a valve chamber, a relatively large vacuum passage communicating with said intake and chamber, a plurality of relatively small passages communicating with said chamber and tank, a relatively small by-pass communicating with said first mentioned passageway and chamber by-passing the end of said passageway entering said chamber, and a valve in said chamber positioned so as to normally rest on the bottom thereof below the mouth of said passageway when the engine is running at high speed, and adapted to be sucked upwardly so as to seat against the mouth of said passageway for closing the same when the engine is running at normal speed soas to cause a suction through said by-pass.

In witness whereof, I have hereunto affiXed my signature.

, HENRY B. COATS. 

